June 18, 2010 | 6
Editor’s Note: A team of researchers led by John Kessler, Texas A&M College of Geosciences chief scientist and assistant oceanography professor, has traveled to the Deepwater Horizon disaster area to study the methane leaking into the Gulf of Mexico (along with tens thousands of barrels of crude oil) daily at the site of the damaged Macondo 252 well. Kessler, along with David Valentine (a professor of marine sediment geochemistry, biogeochemistry and geomicrobiology at the University of California, Santa Barbara) and the rest of his colleagues are hoping to come away with a rough estimate of the spill’s size by the time his team returns home on June 20, followed by more accurate estimates as they complete their analysis of the information collected. Other objectives of the expedition onboard the RV Cape Hatteras include trying to determine how the methane might be removed from the water (whether eaten by waterborne microorganisms or released into the atmosphere) and how methane concentrations will change over time. The following dispatch is Kessler’s second and the team’s fourth blog post overall for Scientific American.
Friday, June 18, 2010
Often times, the most interesting people, places, and things are the ones that on the surface seem bland. But in only the right circumstances with the right people, do these individuals and instances reveal the true complexity of their characters. Finding ourselves in these beautiful situations reminds us how lucky we are to be in such situations of pure truth.
Disregarding the oily surface for now, the natural gas component of this spill is rather uninteresting in the surface waters. Concentrations are near background and at the most a factor of two high. However, the true complexity of this system is revealed down deep. Below approximately 1,000 meters, the concentration of natural gas and methane in the ocean waters jumps by a factor of one million. That’s right, one million. The ramifications of this are the topics of our current studies. The oxygen depletion due to this methane is variable, with some sites displaying 20 percent to 30 percent reductions in oxygen and some having oxygen contents that are seemingly uninfluenced. Our measured rates of methane oxidation by microbiology seem low, but more measurements and calibrations are necessary to confirm this perplexing finding. Each new analysis of this deep water signal reveals a new layer of information that was previously hidden. While this environment is an oily mess, the hidden complexity of the natural gas and methane issue can only be described as beautiful.
Image of Texas A&M graduate student Lei Hu sampling water in front of the Enterprise drill and containment ship, courtesy of John Kessler.